Turbine-control mechanism.



J. N. BAILEY. TURBINE CONTROL MECHANISM,

APPLICATION HLED SEPT. 3,1910.

Patented Jan. 16, 1917.

WITNES E5:

HIS ATTORNEY IN FACT barman smarts onnroa.

JAMES N IGOLSON BAILEY, F STRETFORD, ENGLAND, ASSIGNOR TO THE BRITISHWEST- INGHOUSE ELECTRIC AND MANUFACTURING COMPANY, LIMITED, OF LONDON,

ENGLAND.

TURBINE-CONTROL MECHANISM.

Specification of Letters Patent.

Patented J an. 16, 15917.

Application filed September 3, 1910. Serial No. 580,284.

To all whom it may concern; 7

Beit known that I, JAMES NICOLSON BAILEY, a subject of the King of GreatBritain,and a resident of Stretford, England, have made. a new andusefulInvention in Turbine-Control Mechanism, of which the following isa specification.

This invention relates particularly to systems of marine propulsion ofthe kind in which turbines and electric generators are used for drivingmotors connected with the propellers, the speed of the propellers beingcontrolled by varying thespeed of the turbine and generator, and has.for its ob ject to provide improved means for effecting the braking ofthe rotating element of the turbine.

In power transmission systems of the kind above-mentioned, it isessential to be able to speed up or slow down the turbine quickly and atwill. The turbine is speeded I up' by admitting more steam, while it is3 stopped or slowed down by cutting off the steam and applying abrake.The controller may be operated manually or otherwise. It has beenproposed, therefore, to provide, in addition to what may be termed themain section of the turbine, a braking section comprising a number ofblades, or blades and nozzles, be automatically delivered when thecontroller' is moved from a power position to a lower power position,tion to a stop position in order to effect a braking of the rotatingelement. In this arrangement the admission of's'team to the brakingsection of the turbine is controlled by an electrically operated valvedevice dependent for its operation upon the movement of the controller.

In order that. the nature of the invention the supply of steam totheturbine may be of thetype described in the specification of my EnglishLetters Patent No. 12075 of stituting the braking section of .supply ofinto which steam is adapted to or from a power posi- H 'member isconnected by a link 1908, I have shown valve mechanism of thisdescription for carrying out the invention, and as reference may be hadto that specification only a suflicient portion of the apparatus will bedescribed as will enable the present invention to be clearly understood.

Referring now to the figure, the shaft 2 of the turbine 1 is shownsupported in bearings 3. Mounted upon the shaft 2,;and surrounded by asuitable casing 4c is a disk 5 provided with afseries of blades orprojections 6; similar blades or projections 7 are provided attached tothe wall of the casing, the disk 5 and its surrounding casing contheturbine. The main steam chest of the turbine is shown at 8 connected bymeans of a passage 9 to the source of steam supply and an outlet passage10 is provided leading to the turbine; the flow of steam through thesteam chest being controlled by a main valve 11 and an auxiliary valve12. The auxiliary valve 12 is adapted to cut off the steam to theturbine, irrespective of the position of the main valve 11, whenever thecontroller 13 is moved from a power position to a lower power positionever it is necessary to effect a braking of the turbine, under theaction of a solenoid 13,

the circuit of which is closed whenever this movement of the controlleroccurs. The stem of the valve 12 is connected to one arm of a T shapedmember 14 pivoted at 15 and rotated onits pivot under the action of thesolenoid. The other arm of the T-shaped stem of a piston valve 17, whichis arranged in a cylinder formed within a casing 18. The piston valve 17is provided with an annular groove 19 adapted to establish"communication between ports 20 and 21 or ports 21 and'22 formed in thewall of the casing in accordance with its position in the cylinder. Theport 20 is connected by means of a pipe 23 to the condenser (not shown)and the port 22 is connected by means of a pipe 24 to a source of watersupply, the middle port 21 being connected by means of a pipe 25 to theinterior of the casing 4 in which the disk 5 is located.

An outlet is provided in the casing 18 connected by means of passage 31formed in the wall of the casing to the top and bottom of the cylinderto permit'of drainage 16 to the I from this cylinder, and for balancingthe valve 17.

The interior of the braking section of the turbine isconnected to theatmosphere by means of a passage 26 and pipe 27 connected thereto, theflow of water through this pipe beingcontrolled by means of a manu allyoperated throttle valve 28 and a spring actuated valve device 29. Thelatter of which is adapted to permit the flow of water in one directionbut to be normally retained on its seat under the action of the spring.Under normal conditions, the piston valve 17 will be located at the topof its cylinder and communication will be established between ports 20and 21 so that they braking section of the turbine will be in directcommunication with the condenser.

When the solenoid 13 is energized the T- shaped member 14 will berotated on its ivot, thereby closing the valve 12 cutting off thesupplyof steam. to the turbine and moving the piston valve 17 to thebottom of the cylinder establishing communication between ports 21 and22 and closing the port- 20. Under these conditions, water will besupplied from the port 22 to pipe 25 by means of the annular groove 19in the piston head to the braking section of the turbine and the turbinewill be quickly brought to rest owing to the frictional resistancebetween the water and the rotating disk 51 The projections 6 on the saiddisk are provided to increase this resistance and the projections 7 areadapted to obstruct therotation of the entire volume of water within thecasing under the action of the disk. Suitable packing glands 32 areprovided between the casing 4 and the "turbine shaft to prevent leakageof: water from the braking section which will at the same timeeffectually prevent the entrance of air into the interior .of thecasing. -Sinc, plained, the spring actuated valve device 29 is normallyheld on its seat, under running conditions, when the interior of thecasing L is in communication with the condenser, the valve will beclosed so that the disk 5 will be rotating in vacuo, thereby reducingthe frictional resistance under running conditions to a minimum.

Having now particularly described and ascertained the nature of my saidinvention,

as before eX.-'

and in what manner the same is to be'performed, I declare that what Iclaim is:

1. In combination with a prime mover, means for controlling theoperation of the prime mover, a' liquid brake for said prime mover, andmeans for delivering braking liquid to the brake and-for simultaneouslyactuating the controlling means of the prime mover to shut off theactuating fluid thereto, and for simultaneously actuating thecontrolling means of the prime mover to deliver actuating fluid, and forconnecting the interior of the brake with a region of low pressure.

' 2. In combination with a controlling means therefor, for stopping theprime mover, a valve for delivering braking the brake,

prime mover,

liquid to a liquid brake and means for simultaneously actuating saidvalve and said controlling means to stop said prime mover.

3. In combination with a prime mover, a regulating valvefor controllingthe delivery of motive fluid to the prime mover, an auxiliary ply to theregulating valve and to said prime mover, a liquid brake for the primemover, means for placing the interior of the brake in communication witha region 0 low pressure and for opening the auxiliary valve, and forcutting off communication between theinterior ofthe brake and the regionof low pressure, for delivering liquid to the brake and for closing theauxiliary valve.

4. In combination with a prime mover, a valve for cutting off the supplyof motive fluid to .the prime mover, a liquid brake for stopping theprime mover, means for simultaneously connecting the interior of thebrake to a region of low pressure and for opening said valve, and forsimultaneously cutting off communication between the interior .of thebrake and the region of low ressure, for delivering liquid to said brakeand for closing the valve.

In testimony'whereof I have hereunto subscribed my name this 23rd day ofAugust,

valve for cutting off the fluid sup-

